We already know the fastest, least expensive way to slow climate change: Use less energy. With a little effort, and not much money, most of us could reduce our energy diets by 25 percent or more—doing the Earth a favor while also helping our wallets.

    Not long ago, my wife, PJ, and I tried a new diet—not to lose a little weight but to answer an annoying question about climate change. Scientists have reported recently that the world is bending up even faster than predicted only a few years ago, and that the consequences could be severe if we don't keep reducing emissions(排放) of carbon dioxide (CO₂ ) and other greenhouse gases that are trapping heat in our atmosphere.

    We decided to try an experiment. For one month we recorded our personal emissions of CO₂. We wanted to see how much we could cut back, so we went on a strict diet. The average US household(家庭) produces about 150 pounds of CO₂  a day by doing common-place things like turning on air-conditioning or driving cars. That's more than twice the European average and almost five times the global average, mostly because Americans drive more and have bigger houses. But how much should we try to reduce?

    For an answer, I checked with Tim Flannery, author of The Weather Makers: How Man is Changing the Climate and What it Means for Life on Earth. In his book, he had challenged readers to make deep cuts in personal emissions to keep the world from reaching extremely important tipping points, such as the melting(融化) of the ice sheets in Greenland or West Antarctica. "To stay below that point, we need to reduce CO₂  emissions by 80 percent," he said.

    Good advice, I thought. I'd opened our bedroom windows to let in the wind. We'd gotten so used to keeping our air-conditioning going around the clock. I'd almost forgotten the windows even opened. We should not let this happen again. It's time for us to change our habits if necessary.

    Sometimes when I'm flying from one speaking engagement to another, I find myself sitting next to someone who's quite talkative. This is often a pleasant experience for me because I'm a people-watcher. I learn so much by watching and listening to the people I meet and see every day. I've heard stories of sadness and others of delight, fear and joy, and others that would rival those on “Oprah” and "Geraldo”.

    Sad to say，there are times when I'm sitting next to someone who just wants to vent(发泄） his temper or inflict(强加）his political views on an audience for 600 miles. It was one of those days. I settled in, as my seatmate began his speech on the terrible state of the world with the time worn, “You know, kids today are...” He went on and on, sharing vague notions of the terrible state of teens and young adults, based on watching the six o'clock news rather selectively.

    When I gratefully got off that plane and finally made it to my hotel in Indianapolis, I bought the local paper and went to have dinner in the hotel. There, on an inside page, was an article I believe ought to have been the front-page headline news.

In a little Indiana town, there was a 15-year-old boy with a brain tumor. He was undergoing radiation and chemotherapy(化疗）treatments，As a result of those treatments, he had lost all of his hair. I don't know about you, but I remember how I would have felt about that at his age —I would have felt awkward and ashamed.

    This young man's classmates willingly came to the rescue: all the boys in his grade asked their mothers if they could shave their heads so that Brian wouldn't be the only bald boy in the high school. There, on that page was a photograph of a mother shaving all of her sons' hair with the family looking on approvingly. And in the background, a group of similar bald young men.

    No, I don't despair about kids today.

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    Sometimes I really doubt whether there is love between my parents. Every day they are very busy trying to make money for my schooling.

    One day, my mother was sewing a quilt(缝被子). I silently sat beside her. "Mum, is there love between you and Dad?" I asked in a very low voice.

    With surprise in her eyes, she stopped her work for a while. Then she said, "Susan, look at this thread(线). It can hardly be seen, but it' s really there. It makes the quilt strong. If life is a quilt, love should be a thread. Love is inside. "

    I couldn' t understand her until the next spring. At that time, my father suddenly got sick seriously. My mother had to stay with him in the hospital for a month.

    After they were back, my mother helped my father walk slowly on the country road every day. They were so kind to each other and it seemed they were the happiest couple.

    After two months my father still couldn' t walk by himself. "Dad, how are you feeling now?" I asked him one day.

    "Susan, don' t worry about me," he said. "I just like walking with your mum. I like this kind of life." Reading his eyes, I knew he loves my mother deeply.

    Now I understand that love is just a thread in the quilt of our life. Love is inside, making life strong and warm.

    China became the first country to clone a monkey using non-reproductive cells, scientists said on Thursday. By December 2017 , the Chinese Academy of Sciences had created two clone macaques(猕猴) named“Zhong Zhong” and “Hua Hua”by nuclear transferring of body cells—any cell in the organism other than reproductive cells. This was the similar technology used to create the famous clone sheep Dolly in 1996.

    Telra, a monkey born in 1999 , is the world's first ever-cloned monkey, but it was done using a simpler method called embryo splitting(胚胎分裂)，and cannot be genetically modified to suit experimental needs, said Pu Muming, a leading researcher at the Chinese Academy of Sciences. Cloning a monkey using body cells has been a world-class challenge because it is a primate(灵长类)that shares its genetic makeup, therefore all of its complexity, with humans, he said.

    For drug and other lab tests, scientists have to purchase monkeys from all over the world, which is costly, bad for the environment and produces inaccurate results because each monkey might have different genes, Pu said.

    By cloning monkey using body cells, we can mass reproduce a large number of genetically identical monkeys in a short amount of time, and we can even change their genes to suit our needs, he added. “This can save time, cut down experiment costs, and produce more accurate results, leading to more effective medicine.”

    Sun Qiang, director of the non-human primate research facility at the institute, said most of the drug trials are currently done on lab mice. However, drugs that work on mice might not work or even have severe side effects on humans because the two species are so different.

    Monkeys and humans are both primates, so they are much closely related and testing on monkeys is supposed to be as effective as testing on humans. This achievement will help China lead the world research in an international science project related to study of primate brains.

    A new argument has been put forward as to whether penguins are disturbed by the presence of tourists in Antarctica.

    Previous research by scientists from Keil University in Germany monitored Adelie penguins and noted that the birds' heart rates increased dramatically at the sight of a human as far as 30 meters away. But new research using an artificial egg, which is equipped to measure heart rates, disputes this. Scientists from the Scott Polar Research Institute at Cambridge say that a slow moving human who does not approach the nest too closely, is not viewed as a threat by penguins.

    The earlier findings have been used to partly explain the 20 per cent drop in populations of certain types of penguins near tourist sites. However, tour operators have continued to insist that their activities do not adversely（不利地）affect wildlife in Antarctica, saying they encourage non-destructive behavior in tourists, and that the decline in penguin numbers is caused by other factors.

    Amanda Nimon of the Scott Polar Research Institute spent three southern hemisphere summers at Cuverville Island in Antarctica studying penguin behavior towards humans. “A nesting penguin will react very differently to a person rapidly and closely approaching the nest,” says Nimon. “First they exhibit large and prolonged heart rate changes and then they often flee the nest leaving it open for predators（掠夺者）to fly in and remove eggs or chicks.” The artificial egg, specially for the project, monitored both the parent who had been 'disturbed' when the egg was placed in the nest and the other parent as they both took it in turns to guard the nest.

    However, Boris Culik, who monitored the Adelie penguins, believes that Nimon's findings do not prove his own research invalid. He points out that species behave differently – and Nimon's work was with Gentoo penguins. Nimon and her colleagues believe that Culik's research was methodologically（方法论上）defective because the monitoring of penguins' responses needed catching the birds and fitting them with heart-rate transmitters（发射器）. Therefore, argues Nimon, it would not be surprising if they became stressed on seeing a human subsequently.

    There was a lot of news related to artificial intelligence, or AI, and machine learning. Among the stories were two dealing with direct competitions between humans and machines.

    In one competition, machines that used AI performed better than human beings in a high-level reading test. Two natural language processing tools beat human in the experiment. One of the tools was built by the American technology company Microsoft. The other was created by Chinese online seller Alibaba Group.

    In another competition, a computer took on humans in live, public debates.

    The event demonstrated how AI-powered computers are increasingly being developed to think ' and sound like humans. The organizer of the debates, U. S. technology company IBM, announced split results. It said a majority of those watching said they felt the machine had done more to improve their knowledge of the subject. But, the human got more praise for communicating their ideas.

    This year, we also explored the many ways AI and machine learning are now being used. For example, some U. S. judges use machine learning systems to help them decide when, and for how long, criminals should be jailed. The system uses computers to examine data from thousands of court cases.

    One fast-growing area of AI is facial recognition, which is increasingly being used for security purposes. Recently, Atlanta's Hartsfield-Jackson airport became the first in the U. S. to permit passengers to use facial recognition technology to get on flights. A Chinese company showed off an AI system it developed to recognize individuals by body shape and walking movements. The system is already being used by Chinese police in Beijing and Shanghai.

    In addition, machine learning was used during 2018 to predict results of the World Cup soccer competition. The technology also created artwork that sold for a large amount of money. And it is being used to help farmer save time and money, while reducing environment-harming chemicals. Other technology systems are being used to follow farm animals and wildlife to collect information on their activities.